8b84769a7a
The EFI handover protocol was introduced on x86 to permit the boot loader to pass a populated boot_params structure as an additional function argument to the entry point. This allows the bootloader to pass the base and size of a initrd image, which is more flexible than relying on the EFI stub's file I/O routines, which can only access the file system from which the kernel image itself was loaded from firmware. This approach requires a fair amount of internal knowledge regarding the layout of the boot_params structure on the part of the boot loader, as well as knowledge regarding the allowed placement of the initrd in memory, and so it has been deprecated in favour of a new initrd loading method that is based on existing UEFI protocols and best practices. So update the x86 boot protocol documentation to clarify that the EFI handover protocol has been deprecated, and while at it, add a note that invoking the EFI handover protocol still requires the PE/COFF image to be loaded properly (as opposed to simply being copied into memory). Also, drop the code32_start header field from the list of values that need to be provided, as this is no longer required. Reviewed-by: Borislav Petkov <bp@suse.de> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200409130434.6736-7-ardb@kernel.org
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.